An implant that is embedded into the body (in particular, a dental implant) is attracting attention. In the dental implant, generally, in a case where the tooth root of a permanent tooth has been lost due to dental caries or damage, an implant body is inserted into and fixed to a hole provided at the alveolar bone. The dental implant is configured to include an implant body that is fixed to the alveolar bone, and an abutment which is screwed into the implant body and on which an artificial crown can be mounted.
An implant body described in PTL 1 has a hole portion which is opened at an upper end face thereof. In the hole portion, a hexagonal hole portion and a tapered hole portion are formed. In the implant body, a hexagonal shaft portion that is inserted into the hexagonal hole portion and a tapered shaft portion that comes into contact with the tapered hole portion are formed.
The hexagonal hole portion and the hexagonal axis portion become a rotation-preventing portion. The rotation-preventing portion prevents rotation around a vertical direction with respect to occlusal pressure. The rotation-preventing portion prevents rotation of an abutment with respect to the implant body.
The tapered hole portion and the tapered shaft portion are provided in order to take the occlusal pressure. The tapered hole portion and the tapered shaft portion are formed adjacent to the rotation-preventing portion (the hexagonal hole portion and the hexagonal axis portion).
The tapered shaft portion is fitted into the tapered hole portion in a wedge form by inserting the abutment into the hole portion of the implant body.